Various advances in the technologies that relate to the fabrication and application of solid state memory devices and the applications thereof to circuit design have resulted in numerous circuit arrangements for temporarily or permanently storing digitally encoded data. Although these advances have found widespread application, stringent design restraints have heretofore prevented or substantially limited the use of solid state memory devices for the recording of certain data. One example of a situation wherein solid state memories have not found widespread application is the crash survivable unit of an aircraft flight data recorder system wherein a signal acquisition unit processes various signals that are representative of the flight data to be recorded and supplies various command messages and digitally encoded signals representative of the flight data to the crash survivable memory unit. Since the crash survivable memory unit must retain the stored flight data when subjected to high impact (penetration) forces attendant an aircraft crash and, if the aircraft burns, must retain the stored flight data under exposure to high temperature environment, current flight data recorder crash survivable memory units generally include a penetration-resistant metal housing that contains a mechanism for recording the flight data on magnetic tape. To provide thermal isolation, the magnetic tape mechanism is typically mounted in the central portion of the housing and is encased by insulating material.
Prior art crash survivable memory units of this type exhibit several disadvantages and drawbacks. For example, such memory units are often larger and heavier than desired. Further, because such crash survivable memory units require utilization of numerous precisely machined and precisely mounted components, both the initial cost of the memory unit and the cost of maintenance is higher than desired.